近日，西安交通大学的李蓬勃及其研究小组与福州大学的林励华等人合作并取得一项新进展。经过不懈努力，他们通过耗散实现纠缠生成的条件加速。相关研究成果已于2025年1月2日在国际知名学术期刊《物理评论A》上发表。

本文提出了一种方案，通过向两个耦合量子比特中的一个引入强耗散通道，有条件地加速它们之间量子纠缠的生成。最大纠缠是通过以概率的方式将单个激发在这两个量子比特之间均匀分布来建立的。当初始激发由耗散更强的量子比特持有时，耗散会加速无量子跃迁的量子态轨迹中的激发重分配过程。

研究结果表明，随着耗散速率的增加，有条件地达到最大纠缠所需的时间单调减少，但代价是成功概率迅速降低。研究人员进一步证明，该方案可推广至加速三量子比特系统中W态的产生，其中一个具有强耗散的量子比特对称地与两个具有弱耗散的量子比特耦合。

据悉，耗散通常被视为观察量子效应和利用其进行量子技术开发的不利因素。

附：英文原文

Title: Conditional acceleration of entanglement generation enabled by dissipation

Author: Xiao-Wei Zheng1, Jun-Cong Zheng1, Xue-Feng Pan1, Li-Hua Lin2,*, Pei-Rong Han2,3,†, and Peng-Bo Li1,‡

Issue&Volume: 2025-01-02

Abstract: Dissipation is usually considered a negative factor for observing quantum effects and for harnessing them for quantum technologies. Here, we propose a scheme for conditionally speeding up the generation of quantum entanglement between two coupled qubits by introducing a strong dissipation channel to one of these qubits. The maximal entanglement is established by evenly distributing a single excitation between these two qubits in a probabilistic manner. When the excitation is initially held by the qubit with stronger dissipation, the dissipation accelerates the excitation redistribution process for the quantum state trajectory without quantum jumps. Our results show that the time needed to conditionally attain the maximal entanglement is monotonously decreased as the dissipative rate is increased, at the price of a quickly decreasing success probability. We further show that this scheme can be generalized to accelerate the production of the W state for the three-qubit system, where one qubit with strong dissipation is symmetrically coupled to two qubits with weak dissipation.

DOI: 10.1103/PhysRevA.111.012402

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.111.012402